Dual-function exercisers provide the ability for a user to simultaneously exercise his or her upper and lower body, thus increasing a whole-body workout in reduced time. Many such dual-function exercisers exist on the market today and are widely used in both health clubs and homes. However, the problem remains unsolved as to how to provide an upper body exerciser portion specifically adapted for simultaneous use with a lower body exerciser that both (a) allows a user a fall range of arm movements, including the cycling of hand-grips and/or pull cords in opposition, while also providing adequate and adjustable load forces and a smooth feel to the user, and, (b) reduces maintenance requirements and cost by increasing the cycle life of its parts.
Information potentially relevant to attempts to address these and related problems may be found in U.S. Pat. No. 4,625,962 to Street; U.S. Pat. No. 5,354,251 to Sleamaker; U.S. Pat. No. 5,476,431 to Wilkinson et al.; U.S. Pat. No. 5,527,245 to Dalebout; U.S. Pat. No. 6,123,649 to Lee et al.; U.S. Pat. No. 6,569,065 to Menold et al.; U.S. Pat. No. 6,599,223 to Wang; and U.S. Pat. No. 6,723,028 to Wang et al.; and in U.S. Published Patent Applications 2005/0124471 A1 by Wilkinson et al.; 2005/0130807 by Cutler et al.; and 2005/0209059 A1 by Crawford et al. However, each of these references suffers from one or more of the following disadvantages: (1) they provide dual-function exercisers with only fully independent retraction systems for the upper body portion where the extension of one pull cord has no effect on the position or tensioning of the other, tension in the pull cords increases as the cord is extended, two retraction devices are required, and the retraction devices are cycled (travel) every time the cord is extended which greatly increases the risk of fatigue failure (see, e.g., U.S. Pat. Nos. 4,625,962; 5,354,251; 5,476,431; 6,569,065; 6,723,028; US2005/01244761A1; US 2005/0130807A1; and, US2005/0209059A1); (2) they provide dual-function exercisers with totally dependent pull systems for the upper body portion with no retraction devices in which limiting motion of one arm to the opposition motion of the other arm, many providing only an equal resistance for each arm with pull cables that are not fully retractable (see, e.g., US 2005/01244761A1); (3) they provide dual-function exercisers with semi-dependent resistance systems, but, because the exercise is designed to be a push-pull exercise and because retraction is a secondary function, it is not sufficient to retract pull cords for an upper body portion back to a start position and therefore cannot function to provide a user with a full range of upper body arm movements and exercises (see, e.g., U.S. Pat. No. 5,527,245), or they employ floating pulleys located after the hand grips and before the drive, resistance, and retraction mechanisms, which results in a bypassing of the resistance mechanism when a user tries to cycle the left and right pull cords, removing all loads except for a small retraction force and eliminating adjustability of the load (see, e.g., U.S. Pat. No. 6,599,223); (4) they provide single-function exercisers which are designed for higher loads, slower speeds and fewer repetitions (e.g., certain weight-stack type strength equipment) that would be unsuited to a cardiovascular exercise because the higher weight would exhaust the user too quickly, and the high speed/high frequency repetitions typical in a cardiovascular workout, would produce too much bounce in the weight system; or, (5) they provide single-function exercisers for the lower body only with retraction systems not appropriate to upper body use (see, e.g., U.S. Pat. No. 6,123,649 with fully independent retraction system).
For the foregoing reasons there is a need for an upper body exerciser specifically adapted for use with lower body exercisers which can provide both smooth and varied operation under sufficient load forces substantially constant with extension of a pull cord, while increasing fatigue life and space-efficiency of the unit by reducing travel of its retraction mechanism.